PROJECT SUMMARY/ABSTRACT Memory for events in the recent past is crucial for effective functioning in everyday environments. Imagine someone is retiring and moving to a new city to be with family. Event memory will allow them to remember how to get to the grocery store and in which aisle to look for cereal, which neighbor's child to ask about mowing the lawn, and whether it is late enough to check if the mail has arrived. Failures of event memory are exactly the problems that bring elders into the neurological clinic and raise concerns that they may be developing Alzheimer's disease (AD)?both major epidemiological concerns, given that the population of older adults and the number of people with AD are growing dramatically. However, there is a large gap between this kind of memory and memory as it is usually studied in the psychological and neuroscientific laboratory, by presenting people with disconnected words, pictures, or sentences. Recent empirical and theoretical results have identified specialized neural and computational mechanisms that segment ongoing activity into meaningful events and have shown that these mechanisms are important for memory formation. In this proposal, we describe a novel synthesis and extension of previous approaches to the effects of age and AD on memory, based on these innovations. This synthesis opens up an opportunity to better understand how the mechanisms of human memory encoding change with age and AD, and at the same time to test the potential of novel interventions for potential clinical application to memory improvement. This project will capitalize on this opportunity, achieving three specific aims: Specific Aim 1 will test whether and how attention to event segmentation improves elders' memory for everyday activity at delays from minutes to week. Two well-powered experiments will extend a promising intervention that has been shown to improve event memory in young adults to older adult samples, testing memory at delays up to one month. Specific Aim 2 will test the hypothesis that effective event segmentation improves the resolution of elders' posterior/medial memory representations. Structures in the medial temporal lobes and posterior medial parietal cortex have been shown to be important for event memory and are affected by healthy aging and early AD. Two studies will test whether improving event segmentation improves the resolution of memory representations in these regions. Specific Aim 3 will test whether the mechanisms and consequences of segmentation improvement are maintained or impaired by early symptomatic Alzheimer's disease. Early AD selectively impairs the very systems that are proposed to be important for representing event memories. Two studies will test the possibility that improving event segmentation improves event memory in people with early symptomatic AD.